Web break detection



J n 10, 1958 '0. A. MORLEY 2,838,303

WEB BREAK DETECTION Filed Aug. 21, 1956 2 Sheets-Sheet 1 5* i e Q l\ Qq. i

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59 ORVILLE A. MORLEY LTQBNEYS June 10, 1958 o. A; MORLEY 1 2,838,303

/ WEB BREAK DETECTION Filed Aug. 21, 1956 2 Sheets-Sheet 2 FIG-4 6 IIYVENTOR. ORVILLE A. MORLEY BY WWMQ@ ATTORNEYS United States Patent 6 "iceWEB BREAK DETECTION Orville A. Morley, Dayton, Ohio, assignor to McCallCorporation, Dayton, Ohio, a corporation of Delaware Application August21, 1956, Serial No. 605,404

' 4 Claims. (Cl. 2712.1)

This application relates to a device for detecting a break or hole in aweb of sheet material such as, for example, in a web of paper being fedto a printing press.

The primary object of this invention is to provide a web break detectorwhich will shut down the apparatus to which the web is being supplied,or which will actuate suitable signalling or warning devices, whenever afault, such as a hole, tear, or break is detected in the web of materialbeing fed to the apparatus.

A further object of the invention is to provide a web break detector inwhich the web of material passes over a manifold having longitudinallyaligned openings therein from which a large volume flow of low pressureair is passed to provide an air bearing between the web and themanifold, thereby substantially reducing frictional drag on the web asit passes over the manifold.

Another object of this invention is to provide a web break detector inwhich the web is passed over a supply of low pressure air and in which avane is supported on the opposite side of the web from the air supply,held in spaced relation to the web so as to be insensitive to slightflapping movement of the web, and wherein movement of the vane due topassage of air through a break or hole in the web will result inactuation of an emergency control device.

An additional object of the invention is to provide such a web breakdetector including means for adapting the detector to use with differentwidths of web material.

Another object of the invention is to provide such a web break detectorwhich is adaptable for mounting to address a web traveling in anydirection with respect to vertical, including a counterweight forpositioning the vane which may be adjusted through 360 with respect tothe vane to provide the necessary bias thereon regardless of therelative position of the vane with respect to horizontal.

Other objects and advantages of the invention will be apparent from thefollowing description, the accompanying drawings and the appendedclaims.

In the drawings- Fig. 1 is a front plan view of a web break detector inaccordance with the invention, with certain parts shown in section forpurposes of illustration;

Fig. 2 is a top plan view of the device shown in Fig. 1;

Fig. 3 is an enlarged section taken on line 33 of Fig. 2;

Fig. 4 is a section on line 44 of Fig. 1, with some parts omitted forpurposes of illustration;

Fig. 5 is a section taken on line 55 of Fig. l, with the parts in normalrunning position;

Fig. 6 is a section similar to Fig. 5 showing the parts in positiondetecting a break in the web;

Fig. 7 is a section taken on line 77 of Fig. 1;

Fig. 8 is a view showing the relation between the control actuatingparts, with the vane in the normal position shown in Fig. 5; and

Fig. 9 illustrates the parts in Fig. 8 in a position cor- 2,838,303Patented June 10, 1958 14 for receiving mounting bolts. Each of themounting blocks also includes a generally crescent shaped sector 15removable from the mounting block and held in place by suitable bolts16, providing for adjustment and removal of manifold 10.

Air under pressure is supplied to the interior of manifold 10 from apipe 18 extending from one end of the manifold and adapted forconnection to a suitable source of air under pressure. Such air ispreferably supplied at a pressure of 5 p. s. i. or less, and passes fromthe manifold through a plurality of small holes, slits, or the likegenerally aligned along the manifold and indicated at 20.

The web 25 of sheet material passes over the manifold and over theseholes 20, and the flow of low pressure air from the holes provides anair hearing which eliminates much of the frictional drag which mightresult frompassage of the web over the manifold.

The low pressure air provides a means for detecting breaks, holes, tearsor other such fiaws in the web material as it passes over the manifold.Thus, for example, the detector may be suitably mounted on or adjacentto .a printing press or the like and the web of material to be printedupon can be passed over the manifold as it is supplied to the press. Thepresent detector will then actuate a suitable control means or warningdevice whenever such a flaw in the web of material advancing to the.press permits an air flow through the Web.

The detector apparatus includes a pair of supporting brackets or clamps30 slit at their lower ends and adapted for tightening about manifold 10by a bolt 31 extending through the slit end of the bracket in aconventional manner. These brackets 30 are secured at opposite ends ofmanifold 10 and each bracket includes a mounting hole 32 (Fig. 3) withinwhich a stub shaft 34 is secured by a suitable set screw 35. At one endof shaft 34 there is carried a smaller extension shaft 36 adapted to befixed to the inner race of a conventional ball bearing 38, the outerrace of which is press fitted into counterbored portions 39 at oppositeends of a tubular rod 40. In this manner the rod 40 is'supported inspaced parallel relation to manifold 10, and the web 25 may be passedthrough the space provided between the rod and the manifold.

A vane 45 is secured to rod 40 along a substantial length of the rod andextends laterally from the rod over the holes 20 in manifold 10. Thisvane is preferably supported in spaced relation with respect to web 25so as to be insensitive to slight fluttering or flapping movements ofthe moving web or to changes in thickness of the web resulting, forexample, when a seam in the web material passes over manifold 20. Thisarrangement prevents actuation of the web break detector when a looseweb flaps as it is fed to the press or whena scam in the web materialpasses by the detector. Such controlled sensitivity is a desirablefeature heretofore unavailable in feeler type detectors which includefingers riding directly upon the web, and prevents unnecessary andundesirable actuation of the control means or warning means by thedetector.

The spacing between Web 25 and vane 45 is provided by a stop meansincluding a collar 47 fixed to one end of rod 40 by a suitable set screw48. Stop bolts 50 extend outwardly from collar 47 and are adapted toengage other stop bolts 52 projecting from the face of the adjacent rodmounting bracket 30. As will be apparent from an inspection of Figs. and6,the stop bolts 50 and 52 define the positions of vane 45 and rod 4%)as the normal position, shown in Fig. 5, and as the break detectingposition shown in Fig. 6. i

Movement of vane 45 under the influence of air passmg through a break inthe web, as shown in Fig. 6, will result in a rotation of rod 40 aboutits own axis until movement of the vane is limited by the stop means.Such rotation of rod 40 may be utilized in any convenient way to actuatean appropriate signalling or control means to energize a warning lightor buzzer, or to operate a suitable controller which will shut down thepress so that the imperfect portions of the web may be removed or thecondition remedied in some other way.

A suitable control means may be provided as shown in Figs. 1, 2, 8 and9, wherein a cam 55 is secured to rod 40 by a suitable set screw 56,such cam including a flat portion 58 upon which a roller follower 60rests in the normal position of the rod 40 and vane 45. Follower 60 isarranged to actuate a switch (Fig. 1) which is in turn adapted toactuate a suitable controller, indicated generally at 66, which may bearranged to interrupt feeding of the web material or to actuate awarning device, as may be desired. Switch 65 is supported on a suitableZ-shaped bracket 68 which is fixed to rod supporting bracket 39 bysuitable lock nuts 69 threaded on the stop bolts 52. It will be apparentto those skilled in the art that movement of cam follower 60 may be usedto open or close switch 65 as desired, and depending upon the type ofswitch selected, and that operation of the switch may be employed in anysuitable manner to actuate an emergency control which may be thecontroller or any suitable signalling means.

In order to urge vane 45 into its normalposition shown in Fig. 5, acounterweight 70 is supported upon a rod 72 extending generally radiallyfrom a collar 75 which is in turn fixed to rod 40 by a set screw 76.Weight 70 is also adjustably fixed to rod 72 by a suitable set screw 77.By adjusting the position of collar 75 on rod 40, and appropriatelychanging the distance of weight 70 from collar 75, it is possible tobias rod 40 into the normal operating position shown in Fig. 5regardless of the position in which the entire detector apparatus issupported. In other words, no matter what the angle may be between vane45 and horizontal, it is possible to position the counterweight so thatit will urge rod 40 to rotate toward manifold 10, into the positionshown in Fig. 5, and appropriate adjustment of weight 70 on rod 72 willcompensate for addition or subtraction of the weight of vane 45 to thebiasing force of the counterweight.

The holes or openings 20 are arranged in groups along the length ofmanifold 10, and means are provided for covering one or more of suchgroups of holes when a web of lesser width than the full capacity of thedetector is passed across the manifold. For example, referring to Figs.2 and 7, the holes may be divided into three groups each group of whichis provided with a retractable cover in the form of an elongatedcrescent shaped member, of greater than 180 radial length about manifold10. The inner diameters of such covers are arranged for a sliding fitbetween the cover and the manifold, and a handle 82 is secured to eachcover by a bolt 83, providing for rotation of the cover about themanifold between open and closed positions, as shown by full and dottedlines, respectively, in Fig. 7. Each cover is guided and centered withrespect to its associated group of holes 20 by means of a centering'bolt85 threaded into manifold 10 and passing through an elongated slot 86 inthe cover. Also, each bolt 85 provides an abutment for a spring 87pressing against a shoe 88 for holding the cover in set position uponthe manifold. Therefore, once.

a cover member 89 is moved to a given position the spring and shoe willretain it in such position until the cover is forcibly reset to anotherposition. It will be apparent that by closing one or more of the groupsof holes 20 with an associated cover 80 it is possible to select thedesired effective width of the detector.

The present invention thus provides a web break detector which readilysenses flaws in the moving web due to breaks, holes or the like and yetis insensitive to flapping movements of the web or overlapping seams andthe like. in addition, the detector is adaptable to mounting in aninfinite number of positions ranging from upright to inverted without inany way affecting the operation or sensitivity of the detector.

While the form of apparatus herein described constitutes a preferredembodiment of the present invention, it is to be understood that theinvention is not limited to this precise form of apparatus, and thatchanges may be made therein without departing from the scope of theinvention which is defined in the appended claims.

What is claimed is:

1. A web break detection device comprising means for directing a largevolume flow of relatively low pressure air against the traveling webacross substantially the J entire width thereof, a vane supported on theopposite side of the web from said air directing means and movable underthe pressure of air passing through a break in the web, said vane beingsubstantially equal in length to the width of said web for sensing aflow of air through said web at any position across the width thereof,means urging said vane normally toward said web, stop means positioningsaid vane in spaced relation to the traveling web, said urging meansbeing yieldable under the pressure of air passing through a break in theweb and against said vane, and means operable by movement of said vanefrom its normal position to actuate an emergency control.

2. A web break detection device of the character described comprising atubular manifold having a plurality of openings therein arrangedlongitudinally along one side thereof, means for supporting saidmanifold across the path of travel of the moving web with the moving webcovering said openings, means supplying air under pressure to saidmainfold to provide for a large volume low pressure flow of air throughsaid openings against the web traveling over said manifold, a vanesupported on the opposite side of the web from said openings and adaptedfor movement by the low pressure air emanating from said openings, meanssupporting said vane in spaced relation to said manifold and the web forretaining said vane in a position insensitive to flapping movements ofsaid web, and means operable upon movement of said vane due to pressureof air passing through a break in the web to actuate an emergencycontrol.

3. A web break detection device comprising a tubular manifold memberhaving a plurality of openings therein arranged longitudinally along oneside thereof, means for supporting said member across the path of travelof a moving web of material with said openings directed at the web,means for supplying air under pressure to said manifold to provide for alarge volume low pressure flow of air through said openings against theweb traveling across said manifold, a rod including bearing supports atopposite ends thereof supporting said rod for rotation about its ownaXis, means mounting said bearing supports in spaced relation to saidmanifold for carrying said rod substantially parallel to said manifoldand providing a space between said rod and said manifold for passage ofsaid web, a vane secured along one side thereof to said rod andextending over said openings, means yieldably urging said vane towardsaid manifold providing for swinging movement of said vane away fromsaid manifold under pressure of air passing through an opening in theweband against said vane, a cam fixed to said rod for rotation therewithin relation to swinging movement of said vane, and control meansoperable by said cam in response to rotation of said rod.

4. A web break detection device comprising a tubular manifold memberhaving a plurality of openings therein arranged longitudinally along oneside thereof, means for supporting said member across the path of travelof a moving web of material with said openings directed at the web,means for supplying air under pressure to said manifold to provide for alarge volume low pressure flow of air through said openings against theweb traveling across said manifold, a rod including bearing supports atopposite ends thereof supporting said rod for rotation about its ownaxis, means mounting said bearing supports in spaced relation to saidmanifold for carrying said rod substantially parallel to said manifoldand providing a space between said rod and said manifold for passage ofsaid web, a vane secured along one side thereof to said rod andextending over said openings, stop means defining a normal operatingposition of said vane, a counterweight secured to said rod in spacedrelation to said axis for urging said rod to rotate into said normaloperating position of said vane, said counterweight having an adjustableconnection with said rod providing for movement of said counterweightabout substantially the entire circumference of said rod to provide auniversal adjustment of the effective weight of said counterweight forovercoming the gravitational effects on said vane, said counterweightbeing proportioned in weight to provide for swinging movement of saidvane away from said manifold under pressure of air passing through anopening in the web and against said vane, and means responsive torotation of said rod away from said stop means to operate an emergencycontrol. 1

References Cited in the file of this patent UNITED STATES PATENTS561,772 Dexter June 9, 1896

